Complete staging is mandatory for the management and therapy of neuroendocr
ine tumours, Various radiotracers are available but the best imaging strate
gy has yet to be defined. In this study we retrospectively compared I-123-M
IBG, In-111-[D-Phe(1)]-DTPA-octreotide and F-18-FDG (PET) imaging in 15 pat
ients with metastatic neuroendocrine tumours (11 carcinoid tumours, 4 parag
angliomas). Planar images were acquired 1, 4, 24 and 48 h following the inj
ection of In-111-[D-Phe(1)]-DTPA-octreotide and I-123-MIBG. Whole-body PET
scans were performed 45 min after injection of F-18-FDG. In-111-[D-Phe(1)]
-DTPA-octreotide was positive in 11/15 patients and identified 44 lesions,
F-18-FDG PET was positive in 11/15 patients and identified 107 lesions and
I-123-MIBG was positive in 8/15 patients and identified 67 lesions. No sing
le scintigraphic technique identified all metastatic sites. In one patient
all studies were negative. F-18-FDG PET identified more abnormal sites than
the other two modalities. Combination of all three imaging modalities with
X-ray CT helps to provide a more comprehensive map of the disease.